3945521980 has 24 divisors (see below), whose sum is σ = 8304749712. Its totient is φ = 1574560512.

The previous prime is 3945521939. The next prime is 3945521999. The reversal of 3945521980 is 891255493.

It is a self number, because there is not a number n which added to its sum of digits gives 3945521980.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 219142 + ... + 236461.

It is an arithmetic number, because the mean of its divisors is an integer number (346031238).

Almost surely, 2^3945521980 is an apocalyptic number.

It is an amenable number.

3945521980 is an abundant number, since it is smaller than the sum of its proper divisors (4359227732).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3945521980 is a wasteful number, since it uses less digits than its factorization.

3945521980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 456045 (or 456043 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 46.

The square root of 3945521980 is about 62813.3901329963. The cubic root of 3945521980 is about 1580.1615468000.

The spelling of 3945521980 in words is "three billion, nine hundred forty-five million, five hundred twenty-one thousand, nine hundred eighty".